[fio.git] / lib / rand.h

#ifndef FIO_RAND_H
#define FIO_RAND_H

#include <inttypes.h>
#include "types.h"
#include "../arch/arch.h"

#define FRAND32_MAX	(-1U)
#define FRAND64_MAX	(-1ULL)

struct taus88_state {
	unsigned int s1, s2, s3;
};

struct taus258_state {
	uint64_t s1, s2, s3, s4, s5;
};

struct frand_state {
	unsigned int use64;
	union {
		struct taus88_state state32;
		struct taus258_state state64;
	};
};

struct frand64_state {
	uint64_t s1, s2, s3, s4, s5;
};

static inline uint64_t rand_max(struct frand_state *state)
{
	if (state->use64)
		return FRAND64_MAX;
	else
		return FRAND32_MAX;
}

static inline void __frand32_copy(struct taus88_state *dst,
				  struct taus88_state *src)
{
	dst->s1 = src->s1;
	dst->s2 = src->s2;
	dst->s3 = src->s3;
}

static inline void __frand64_copy(struct taus258_state *dst,
				  struct taus258_state *src)
{
	dst->s1 = src->s1;
	dst->s2 = src->s2;
	dst->s3 = src->s3;
	dst->s4 = src->s4;
	dst->s5 = src->s5;
}

static inline void frand_copy(struct frand_state *dst, struct frand_state *src)
{
	if (src->use64)
		__frand64_copy(&dst->state64, &src->state64);
	else
		__frand32_copy(&dst->state32, &src->state32);

	dst->use64 = src->use64;
}

static inline unsigned int __rand32(struct taus88_state *state)
{
#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)

	state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12);
	state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4);
	state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17);

	return (state->s1 ^ state->s2 ^ state->s3);
}

static inline uint64_t __rand64(struct taus258_state *state)
{
	uint64_t xval;

	xval = ((state->s1 <<  1) ^ state->s1) >> 53;
	state->s1 = ((state->s1 & 18446744073709551614ULL) << 10) ^ xval;

	xval = ((state->s2 << 24) ^ state->s2) >> 50;
	state->s2 = ((state->s2 & 18446744073709551104ULL) <<  5) ^ xval;

	xval = ((state->s3 <<  3) ^ state->s3) >> 23;
	state->s3 = ((state->s3 & 18446744073709547520ULL) << 29) ^ xval;

	xval = ((state->s4 <<  5) ^ state->s4) >> 24;
	state->s4 = ((state->s4 & 18446744073709420544ULL) << 23) ^ xval;

	xval = ((state->s5 <<  3) ^ state->s5) >> 33;
	state->s5 = ((state->s5 & 18446744073701163008ULL) <<  8) ^ xval;

	return (state->s1 ^ state->s2 ^ state->s3 ^ state->s4 ^ state->s5);
}

static inline uint64_t __rand(struct frand_state *state)
{
	if (state->use64)
		return __rand64(&state->state64);
	else
		return __rand32(&state->state32);
}

static inline double __rand_0_1(struct frand_state *state)
{
	if (state->use64) {
		uint64_t val = __rand64(&state->state64);

		return (val + 1.0) / (FRAND64_MAX + 1.0);
	} else {
		uint32_t val = __rand32(&state->state32);

		return (val + 1.0) / (FRAND32_MAX + 1.0);
	}
}

/*
 * Generate a random value between 'start' and 'end', both inclusive
 */
static inline int rand_between(struct frand_state *state, int start, int end)
{
	uint64_t r;

	r = __rand(state);
	return start + (int) ((double)end * (r / (rand_max(state) + 1.0)));
}

extern void init_rand(struct frand_state *, bool);
extern void init_rand_seed(struct frand_state *, unsigned int seed, bool);
extern void __fill_random_buf(void *buf, unsigned int len, unsigned long seed);
extern unsigned long fill_random_buf(struct frand_state *, void *buf, unsigned int len);
extern void __fill_random_buf_percentage(unsigned long, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int);
extern unsigned long fill_random_buf_percentage(struct frand_state *, void *, unsigned int, unsigned int, unsigned int, char *, unsigned int);

#endif
Commit	Line	Data
1fbbf72e JA	1	#ifndef FIO_RAND_H
	2	#define FIO_RAND_H
	3
c3546b53	4	#include <inttypes.h>
de4096e8	5	#include "types.h"
16dc0710 JA	6	#include "../arch/arch.h"
16dc0710 JA	7
c3546b53 JA	8	#define FRAND32_MAX (-1U)
c3546b53 JA	9	#define FRAND64_MAX (-1ULL)
2615cc4b	10
c3546b53	11	struct taus88_state {
1fbbf72e JA	12	unsigned int s1, s2, s3;
	13	};
	14
c3546b53 JA	15	struct taus258_state {
	16	uint64_t s1, s2, s3, s4, s5;
	17	};
	18
	19	struct frand_state {
	20	unsigned int use64;
	21	union {
	22	struct taus88_state state32;
	23	struct taus258_state state64;
	24	};
	25	};
	26
	27	struct frand64_state {
	28	uint64_t s1, s2, s3, s4, s5;
	29	};
	30
	31	static inline uint64_t rand_max(struct frand_state *state)
	32	{
	33	if (state->use64)
	34	return FRAND64_MAX;
	35	else
	36	return FRAND32_MAX;
	37	}
	38
	39	static inline void __frand32_copy(struct taus88_state *dst,
	40	struct taus88_state *src)
	41	{
	42	dst->s1 = src->s1;
	43	dst->s2 = src->s2;
	44	dst->s3 = src->s3;
	45	}
	46
	47	static inline void __frand64_copy(struct taus258_state *dst,
	48	struct taus258_state *src)
5c94b008 JA	49	{
	50	dst->s1 = src->s1;
	51	dst->s2 = src->s2;
	52	dst->s3 = src->s3;
c3546b53 JA	53	dst->s4 = src->s4;
c3546b53 JA	54	dst->s5 = src->s5;
5c94b008 JA	55	}
5c94b008 JA	56
c3546b53 JA	57	static inline void frand_copy(struct frand_state dst, struct frand_state src)
	58	{
	59	if (src->use64)
	60	__frand64_copy(&dst->state64, &src->state64);
	61	else
	62	__frand32_copy(&dst->state32, &src->state32);
	63
	64	dst->use64 = src->use64;
	65	}
	66
	67	static inline unsigned int __rand32(struct taus88_state *state)
1fbbf72e JA	68	{
	69	#define TAUSWORTHE(s,a,b,c,d) ((s&c)<<d) ^ (((s <<a) ^ s)>>b)
	70
	71	state->s1 = TAUSWORTHE(state->s1, 13, 19, 4294967294UL, 12);
	72	state->s2 = TAUSWORTHE(state->s2, 2, 25, 4294967288UL, 4);
	73	state->s3 = TAUSWORTHE(state->s3, 3, 11, 4294967280UL, 17);
	74
	75	return (state->s1 ^ state->s2 ^ state->s3);
	76	}
	77
c3546b53 JA	78	static inline uint64_t __rand64(struct taus258_state *state)
	79	{
	80	uint64_t xval;
	81
	82	xval = ((state->s1 << 1) ^ state->s1) >> 53;
	83	state->s1 = ((state->s1 & 18446744073709551614ULL) << 10) ^ xval;
	84
	85	xval = ((state->s2 << 24) ^ state->s2) >> 50;
	86	state->s2 = ((state->s2 & 18446744073709551104ULL) << 5) ^ xval;
	87
	88	xval = ((state->s3 << 3) ^ state->s3) >> 23;
	89	state->s3 = ((state->s3 & 18446744073709547520ULL) << 29) ^ xval;
	90
	91	xval = ((state->s4 << 5) ^ state->s4) >> 24;
	92	state->s4 = ((state->s4 & 18446744073709420544ULL) << 23) ^ xval;
	93
	94	xval = ((state->s5 << 3) ^ state->s5) >> 33;
	95	state->s5 = ((state->s5 & 18446744073701163008ULL) << 8) ^ xval;
	96
	97	return (state->s1 ^ state->s2 ^ state->s3 ^ state->s4 ^ state->s5);
	98	}
	99
	100	static inline uint64_t __rand(struct frand_state *state)
	101	{
	102	if (state->use64)
	103	return __rand64(&state->state64);
	104	else
	105	return __rand32(&state->state32);
	106	}
	107
e7b24047 JA	108	static inline double __rand_0_1(struct frand_state *state)
	109	{
	110	if (state->use64) {
	111	uint64_t val = __rand64(&state->state64);
	112
592bf458	113	return (val + 1.0) / (FRAND64_MAX + 1.0);
e7b24047 JA	114	} else {
	115	uint32_t val = __rand32(&state->state32);
	116
592bf458	117	return (val + 1.0) / (FRAND32_MAX + 1.0);
e7b24047 JA	118	}
	119	}
	120
e0a04ac1 JA	121	/*
	122	* Generate a random value between 'start' and 'end', both inclusive
	123	*/
	124	static inline int rand_between(struct frand_state *state, int start, int end)
	125	{
	126	uint64_t r;
	127
	128	r = __rand(state);
	129	return start + (int) ((double)end * (r / (rand_max(state) + 1.0)));
	130	}
	131
de4096e8 JA	132	extern void init_rand(struct frand_state *, bool);
de4096e8 JA	133	extern void init_rand_seed(struct frand_state *, unsigned int seed, bool);
7d9fb455	134	extern void __fill_random_buf(void *buf, unsigned int len, unsigned long seed);
3545a109	135	extern unsigned long fill_random_buf(struct frand_state , void buf, unsigned int len);
bc769898	136	extern void __fill_random_buf_percentage(unsigned long, void , unsigned int, unsigned int, unsigned int, char , unsigned int);
d1af2894	137	extern unsigned long fill_random_buf_percentage(struct frand_state , void , unsigned int, unsigned int, unsigned int, char *, unsigned int);
1fbbf72e JA	138
1fbbf72e JA	139	#endif